JPS6145040B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an excavated soil amount measuring device for an earth pressure type shield excavator.

An earth pressure type shield excavator divides an earth pressure chamber between a cutter and a bulkhead, and continuously pumps earth and sand while retaining the earth and sand taken into the earth pressure chamber by the cutter until it is almost full. It is excavated and excavated. The discharge of earth and sand is carried out by a screw conveyor that penetrates the partition wall and opens at one end into the earth pressure chamber, while maintaining earth pressure against the earth pressure on the ground.

In the shield excavator as described above, excavation management is performed by measuring the amount of excavated soil and comparing the measured value with a design amount of soil (volume obtained by multiplying the excavation cross-sectional area by the excavation length). When measuring the amount of excavated soil,
Conventionally, this was measured by weight, and either the measured value was divided by a preset density of the soil, or the design amount of sand was multiplied by the set density and the two were compared. However, the true soil density changes as the shield excavator excavates, and if the difference between the true soil density and the set density becomes large, the value obtained by dividing the amount of excavated soil by the set density or the design soil The problem was that the error in the value multiplied by the density increased, making accurate excavation management impossible.

In addition, when measuring the amount of excavated soil by weight, a method is generally used in which an earth and sand carrier containing the excavated soil is mounted on a load cell, but in this case, the measuring device including the load cell is large. It had the disadvantage of becoming.

This invention eliminates the conventional drawbacks as mentioned above,
To provide a measuring device capable of managing excavation without being affected by changes in the density of earth and sand by measuring the amount of excavated earth and sand not by weight as in the conventional method but by volume.

That is, in this invention, a discharge pipe equipped with a gate operated by an operating member is installed at the other end of the earth and sand discharge member, one end of which opens in the earth pressure chamber partitioned between the cutter and the partition wall, and this discharge pipe is provided with a gate operated by an operating member. In an earth pressure type shield excavator configured to discharge excavated earth compacted by the earth and sand carrying member from a cylinder,
A member for measuring the gate opening is provided in the gate operating member, an earth pressure gauge is installed in the discharge tube, and a sediment current meter is installed in the discharge tube, and the gate opening degree measuring member and the current meter are installed in the discharge tube. A first calculating member receives the respective outputs and calculates the apparent amount of sediment, and each output of the first calculating member and the earth pressure meter is inputted, and calculates the ratio between the output of the earth pressure meter and the set earth pressure value. In addition, the present invention is characterized in that a second calculation member is provided that calculates the amount of sand by multiplying the output of the first calculation member by the ratio.

The invention will be described below with reference to embodiments shown in the drawings.

As shown in FIG. 1, the earth pressure type shield excavator 1 includes a cutter 3 and a partition wall 4 at the front end of a main body 2, and an earth pressure chamber 5 is defined between the two. A screw conveyor 6 is disposed in the earth pressure chamber 5 through the partition wall 4.
One end protrudes, and an inlet 7 for excavated earth and sand is provided at this one end. A discharge tube 8 having a square cross section is provided at the other end of the screw conveyor 6, and a gate 9 passing through one side wall of the discharge tube 8 is provided. The gate 9 is connected to an operating rod 11 of a jack 10 attached to the screw conveyor 6, and moves in a direction across the discharge pipe 8 by the operation of the jack 10 to adjust the flow path cross-sectional area of the earth and sand flowing through the discharge pipe 8. It's becoming like that.

The flow passage cross-sectional area of the discharge tube 8 is determined by the product of the gate opening degree a and the fixed dimension b of the discharge tube 8, as shown in FIGS. A detection member (not shown) is provided at the.

An earth pressure gauge 12 is installed inside the discharge pipe 8, and this earth pressure gauge 12 is designed to maintain the earth pressure value inside the discharge pipe 8 at a set earth pressure value (earth pressure value approximately equal to the ground pressure at the face). The opening/closing and opening degree of the gate 9 is controlled.

A Doppler current meter 13 is attached to the side wall of the discharge pipe 8 facing the gate 9, and this current meter 13 is adapted to detect the flow velocity of the earth and sand flowing in the flow path defined by the gate 9. There is.

In Fig. 1, 14 is the shield excavator main body 2
15 is a shield segment, and 16 is a belt conveyor that transports the earth and sand discharged from the discharge tube 8.

Next, the mechanism for measuring excavated soil will be explained with reference to the block diagram shown in FIG. In FIG. 4, the part surrounded by the chain line shows the entire arithmetic device.

The output signal of the current velocity meter 13 is inputted to the apparent sediment calculator 19 via the converter 17, and the output signal of the setting device 18, in which the fixed dimension b of the discharge tube 8 is set, and the gate opening are input to the calculator 19. degree detection member 10
The output signal from a is input, and the apparent amount of sediment is calculated.

The earth and sand calculator 20 includes a calculator 19 and an earth pressure gauge 12.
The output signal of is input. The earth and sand calculation unit 20 calculates the ratio between the set earth pressure value inputted in advance to the earth pressure value measured by the earth pressure meter 12, and multiplies the output signal of the calculation unit 19 by this ratio to calculate the amount of earth and sand. The output signal of the calculator 20 is input to the integration display 23, and the integrated value of the amount of excavated earth and sand with respect to the excavation length or time is displayed in volume on this display 23.

Further, the output signal of the calculator 20 is inputted to a comparison display 21, and the amount of excavated earth and sand per 1 cm of excavation length is integrated and displayed on this display 21. Similarly,
The output signal of the design sediment amount calculator 22 is input to the comparison display 21, and the integrated value of the set sediment amount is displayed on the display 21 for every 1 cm of excavation length. The set sediment amount calculator 22 includes a setter 2 in which the excavation cross-sectional area is set.
The output signal of No. 4 and the output signal of the propulsion speed detection member 14a provided on the propulsion jack 14 are input, and the design soil amount is calculated. FIG. 5 shows an example of the amount of excavated earth and sand displayed on the display 21 and the amount of designed earth and sand.

The true excavated soil amount calculated by the above measuring mechanism is expressed by the following formula.

G ₁ = a × b × v ₁ × γ ………(1) In equation (1), G ₁ is the true excavated soil volume (m ³ /min), a
is the gate opening degree (m), b is the fixed dimension of the discharge tube 8 (m), v ₁ is the flow velocity (m/min), and γ is the ratio between the measured earth pressure value and the set earth pressure value. a x b x v ₁ is nothing but the apparent sediment volume, and multiplying this by γ means that when the gate 9 opens and the earth pressure in the discharge tube 8 falls below the set earth pressure value, the volume will be the set earth pressure value. By becoming larger than the original one.

In addition, the set sediment value is expressed by the following formula.

G ₂ = S × v ₂ ...... (2) In equation (2), G ₂ is the design soil volume (m ³ /min), S is the excavation cross-sectional area (m ² ), and V ₂ is the propulsion speed (m/min). ).

This invention is as described above, and since the amount of excavated soil is measured by volume rather than by weight as in the conventional method,
There are no errors caused by changes in the density of the earth and sand, so accurate excavation management can be performed, and the equipment itself does not need to be large because all you have to do is attach the various equipment. can be effectively used for other purposes.

[Brief explanation of the drawing]

Fig. 1 is a front sectional view of the shield excavator of the present invention, Fig. 2 is a front sectional view of the discharge tube, Fig. 3 is a side sectional view of the same, Fig. 4 is a block diagram of the measuring mechanism, and Fig. 5. The figure shows a display example of a comparison between the amount of excavated earth and sand and the amount of designed earth and sand. 1...Shield excavator, 3...Katsuta, 4...
Partition wall, 5...Earth pressure chamber, 6...Screw conveyor (earth and sand carrying member), 8...Discharge pipe, 9...Gate,
10...Gate jack, 12...Earth pressure gauge, 13
...Dotsupura current meter, 19... Apparent sediment amount calculator (first calculation member), 20... True sediment amount calculator (second calculation member).

Claims (1)

[Claims] 1. A discharge tube equipped with a gate operated by an operating member is installed at the other end of the earth and sand transport member, one end of which opens in the earth pressure chamber partitioned between the cutter and the partition wall, and the earth and sand are discharged from this discharge tube. In an earth pressure type shield excavator configured to discharge excavated soil compacted by a carry-out member, a member for measuring the gate opening is provided in the operating member of the gate, and an earth pressure gauge is installed in the discharge tube. At the same time, a sediment current meter is installed in the discharge pipe, and further includes a first calculation member that receives each output of the gate opening measurement member and the current meter to calculate an apparent sediment amount, and the first calculation member and a second calculation member into which each output of the earth pressure meter is input, calculates a ratio between the output of the earth pressure meter and a set earth pressure value, and calculates a true earth and sand amount by multiplying the output of the first calculation member by the ratio; An excavated soil amount measuring device for an earth pressure shield excavator, characterized by being provided with.